Link Foundation Fellowships Newsletter

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Meet this Year's Fellowship Recipients

Link Fellowship Awardees For 2012

Energy

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Name: Gairik Sachdeva
Department: Engineering and Applied Sciences
School: Harvard University
Project: Synthetic Metabolic Control for Biofuel Production
Research Advisor: Prof. Pamela Silver

As a Link Foundation Energy Fellow I will work with a combination of novel synthetic biology and computational approaches to engineer cellular metabolic pathways for redirecting biochemical fluxes towards the production of biofuels. While the biosphere is replete with solar energy, the primary challenge is to channel it into liquid fuel molecules usable with current infrastructure. In addition to traditional genetic engineering techniques, "coercing" cells to produce biofuels requires deep understanding of the complexity of naturally evolved regulation and development of tools to enable directed control.

Compartmentalization is a powerful strategy for metabolic control used widely in eukaryotes.  Bacterial cells, although simpler to engineer, lack compartments barring few examples. My research will try to show that carefully designed RNA strands expressed genetically can be used as intracellular scaffolds for metabolic enzymes, greatly enhancing pathway flux. These RNA are invivo assembled, stable, one or two-dimensional structures that offer multiple binding sites to specific enzymes. By spatially insulating metabolic reaction centers, the scaffolds can mimic organellar compartmentalization. I aim to exploit this tool and establish its utility experimentally in the following:

  1. Increasing bacterial biofuel yields
  2. Creating modular synthetic carbon fixation units
  3. Controlling directionality of reactions toward high value chemicals

 

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Name: Daniel Andrew Krest Schnitzer
Department: Engineering and Public Policy
School: Carnegie Mellon University
Project:Measuring and Modeling the Effects of Energy Efficiency and Renewable Energy on Microgrid Operational Performance and Community Welfare in Haiti
Research Advisor: Jay Apt

Energy poverty – the circumstance of depending on expensive, inefficient, and unproductive energy fuels and technologies that are harmful to human health and the environment – is rampant globally and especially so in Haiti.  More than 75% of Haitians live without access to electricity, and the average household spends 10% of its income on kerosene and candles for lighting.   Micro-grids can be effective solutions to energy poverty, and thousands currently provide electricity to low-income communities throughout Asia, Africa and South America.

However, these micro-grids are frequently characterized by low cost recovery, low availability, and high operating costs.  My research aims to identify financially sustainable interventions to improve those metrics, and a practical method for determining those interventions.  That method is similar to the portfolio approach taken by utilities in industrialized countries to obtain “least cost” electricity service that includes both demand-side (e.g., efficient light bulbs) and supply-side (e.g., wind power) options.  For example, this method may determine that replacing incandescent light bulbs with LED bulbs in a micro-grid that provides power 20 hours a week could yield an additional 5 hours per week at no additional cost.

A concerted effort will be made to coordinate with international micro-grid practitioner networks to ensure that lessons learned from this research are promulgated and adopted in the field.

 

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Name: Huiliang (Evan) Wang
Department:Department of Materials Science and Engineering
School:Stanford University
Project:Semiconducting polymer assisted separation of semiconducting carbon nanotubes for high efficiency hybrid photovoltaics
Research Advisor:Professor Zhenan Bao

Currently, conventional silicon photovoltaics (PV) are too expensive to compete with fossil fuels due to their tedious high temperature processing. Solution processed organic photovoltaic, in contrast, exhibit advantages such as low cost, ready availability, light weight, flexibility and stretchability. However, the efficiency organic solar cell is restricted by the relatively low hopping transport of fullerene. Single-walled Carbon nanotubes (SWNTs) are promising to replace fullerene derivatives due to their high charge carrier mobility and high aspect ratio for forming a conductive percolation network for charge transport. However, the current SWNTs/polymer solar cells suffer from rather low efficiencies due to the light harvesting properties of SWNTs and the charge separation process at SWNTs/polymer interface.

In the project, I will study these processes by selectively dispersion of SWNTs with controlled bandgap and electronic types through helical wrapping of SWNTs by rationally designed conjugated polymers. Our group has already achieved the separation of semiconducting SWNTs from the metallic ones by polythiophenes. This process will eliminate the metallic SWNTs, which act as a charge carrier recombination center and cause inefficient charge separation. By further controlling the semiconducting SWNTs bandgap using specifically designed polymers, we will enhance our understanding of the key processes in SWNTs based solar cells and ultimately realize high efficiency, low-cost, solution-processed solar cells.